Confused about Lower Control Arms compatibility, someone please help!

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iNFiNiTY125

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The forged arms are not 99 only. They started earlier, but I'm unsure of the year. If by "ready set" you mean a new after market part, you won't find that. Lower control arms are not available for our trucks like that. That's a fairly recent way to sell parts. The whole arm was not designed to be a wear part, but to have the wear parts replaced... ball joint and bushings.

99-06 would have to be GMT-800 stuff and is not what you would want.

Given all that you wrote about the things you've tried to do, to remove the rivets, and all that you've purchased, I would seriously consider paying a shop to the job.


I also considered taking it to a shop, but it is far too taken apart to move, I called all the local shops near me, all of them except one refused the job, the only shop that said they would do it wants $1100 to replace the lower ball joints with rivets. I only paid 1500 for the whole truck...


I don't think the lower ball joints were designed to be removed, otherwise they would have used bolts. All data says the job is to replace both LCA's but they dont sell them anymore. Do you think a plasma cutter would get them out?

So really my only option is to get a busted set of 512-01592L and 512-01591R and then replace the ball joints and bushings? Im just afraid I will be stuck in the same situation. I really just want a drop in replacement new/ rebuilt whatever just anything I can use?
 

Supercharged111

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MSCustoms

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The forged arms from a gmt400 are direct bolt in. They started in 95 or 96 in the K2500 trucks or suburbans. I ended up needing a hydraulic press to get the ball joints in and out and the stock bushings as well but only because my c-clamp did not have enough stroke.

I would not try the gmt800 lca's because the geometry probably isnt right.
 

pap-repair

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Always check for the Hollender Interchange #. I use :
http://www.autoparthotline.com/hollander.htm to get the prefix and then
https://www.hollanderparts.com/ to get this number using the search function.
For your 91 K2500, I found for the front LCAs
512-01037Al Left 4X4
512-01037Ar Right 4X4

I do not know if these are stamped or forged.

Now check eBay or the above website to buy.

Hope this helps,
Peter

 

Seaurchin1969

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The best way to remove the riveted BJ's is to use a grinder to cut an X in the head of the rivet on the top side, cut the head off with a air chisel and then drill a 1/4" hole down into the rivet but DO NOT drill all the way through. Then take a punch in your air hammer and push the rivets out the bottom of the LCA. the reason for pushing the rivet out from top to bottom is the rivet has a stepped shank( it is larger on the bottom than the top)
I have done hundreds of these Ball Joints under warranty at the dealership back in the late 80's,early 90's and this is the fastest way I found of doing them, after a little practice you should be able to knock them out in under 30 minutes without to much trouble

if this method is correct, and going by the picture you posted, you are working the bottom side of the control arm. According to the above quote, you are driving the rivets the wrong way.

"the reason for pushing the rivet out from top to bottom is the rivet has a stepped shank( it is larger on the bottom than the top)"

hope that helps, fresh eyes can see what you are missing.
 

454cid

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if this method is correct, and going by the picture you posted, you are working the bottom side of the control arm. According to the above quote, you are driving the rivets the wrong way.

"the reason for pushing the rivet out from top to bottom is the rivet has a stepped shank( it is larger on the bottom than the top)"

hope that helps, fresh eyes can see what you are missing.

No, the ball joints point down on a 4x4.
 

Schurkey

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GM has riveted ball joints since Fido was a pup. I had a '66 Biscayne that had riveted ball joints, and riveted ball joints wasn't a new process even then.

Rivets cost less than nuts and bolts, and once installed, can't come loose and cause warranty or safety concerns.

You've bought two air hammers. What compressor are you powering them with? When I popped the rivets from my '88, I had a 3 hp, 20 gallon tank. I could air hammer for about three seconds before the air pressure was so low there was no point to continuing. Air tools need 90 psi at the tool, with the tool running. That generally means 135 psi in the tank with the regulator as high as it will go; and that's more than some compressors can manage; and more than some regulators will provide. MORE than 90 psi at the tool, with the tool running can be beneficial but it must violate some OSHA regulation, 'cause most air tools are rated for 90 psi max.

Take a close look at your control arm bushings. They're almost guaranteed to be completely rotted, maybe even torn. You might as well pull the control arm free of the frame, and torch the rubber out of the shells. (DON"T remove the shells.) Then install Polyurethane bushings that don't deteriorate like rubber does.

No, it's not fun. Especially if the torsion bar won't release from the control arm. It is possible, though.

If they do release from the torsion bar, you can carry the control arms to a shop that has a hydraulic press, and pop those rivets right out.
 
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